Passenger vehicles often include electric batteries for operating features of a vehicle's electrical and drivetrain systems. For example, vehicles commonly include a 12V lead-acid automotive battery configured to supply electric energy to vehicle starter systems (e.g., a starter motor), lighting systems, and/or ignition systems. In electric, fuel cell (“FC”), and/or hybrid vehicles, a high voltage (“HV”) battery system (e.g., a 360V HV battery system) may be used to power electric drivetrain components of the vehicle (e.g., electric drive motors and the like). For example, an HV rechargeable energy storage system (“RESS”) included in a vehicle may be used to power electric drivetrain components of the vehicle.
In certain designs, battery systems included in a vehicle may include one or more subdivisions or sections. For example, a vehicle battery system may include a battery pack that comprises one or more subdivisions of battery cells. Battery subdivisions may be replaced and/or added in a battery pack, resulting in differences in capacities, state of charge, discharge rates, impedances, and/or voltages between the new battery subdivisions and the existing battery subdivisions. Similarly, a battery cell may be replaced and/or added in a battery subdivision, resulting in differences in capacities, state of charge, discharge rates, impedances, and/or voltages between the new battery cell and the existing battery cells.
Battery discharge may terminate when at least one subdivision of the battery is depleted or at a threshold established by a battery control system. The threshold for terminating further discharge may be based upon monitoring the voltage or other parameters of the battery as a whole. Failure to restrict further discharge of the battery below an over-depletion threshold may result in battery system inefficiencies, degradation, permanent damage and/or a shortened usable lifespan.